Heating system



N. L. DERBY HEATING SYSTEM March 3, 1931.

Filed Feb. 8, 1928 Patented Mar. 3, 1931 UNITED STATES PATENT OFFICE Application and rebruary s, was. semi N. 25am.

The general object of my` present invention is to provide an improved heating sys-- tem for vehicles having an internal combustion engine as a source of motive power. More specifically, the object of my invention is to provide a heating sy-stem operating under a pressure normally below atmospheric and provided with means for automatically regu ating the amount of Huid in circulation in accordance with the fluid pressure in the system.

The various features of novelty which characterize my invention are pointed out with particularity -in the claims annexed to and formin a part of this specication. For a better un erstanding of theinvention, however, and the advantages possessed by it reference should be had to the accompanyin drawing and .descriptive matter lin whic I have illustrated and described a preferred embodiment of the invention.

Of the drawing:

Fig. 1 is an elevation partly in section of a preferred embodiment of my invention;

' Fig. 2 is a section through the control valve shownv in Fig. 1; and i Fig. 3 is a section through the valve ports of Fig. 2.

In the drawing and particularly in Fig. 1, I have illustrated a preferred embodiment of my invention in which A is a radiator casing having a multiplicity of perforations A therein for the circulation of air. The casing is transversely mounted on and secured to the flooring B of an automobile orllke vehicle in any7 suitable manner. Openings B are formed 1n the flooring for the entrance l of fresh air to the radiator unit.

A radiator unit C is mounted in the casing A and comprises a tubelC supported in an inclined position by casing brackets A? and A8. -A concentric tube C is arranged within the tube C. An annular lug Ca is mounted in each end of the tube and presvides` a gas-tight annular space Cbetween the tubes C and C2. A continuous radiating lin C5 is secured circumferentially of the tube C and extends substantially the length'thereof. A vertical pipe D -1passing down through f )ne of the openings vin the vehicle flooring connects the lower end of the radiator .unit to a heating unit utilizing as a sourceof heat the exhaust gases from thevehicle engine;

In the construction shown the heating unit comprises an inverted T-,shaped casing E 1nserted in and forming a part of the engine exhaust pipe E. A cover late E2 prevents the escapel of ases throug the top of the casing L. A ollow vcylindrical casingEa is mounted on the bottom plate of the casing i and spaced from the top and sides thereof. Remova ly secured to the underside of the bottom plate is a hollow longitudinally ex- `'pansible and collapsible element F, preferably in the form of a metallic bellows or an ,air tight waterproof textile fabric bellows reinforced by a Icoiled spring. In Fig. l the element is shown as a seamless metallic bellows having toand bottom plates F and F2, respectively. he to plate F is provided with a central threa ed opening to which a T F 8 mounted in the casing Es lis connected by a nipple. A vertical' pi G has its lower end connected to the T an its upper end to a nipple G secured in the casing cover plate E2. The T and nipple are also connected by a coiled pi e G2 used as the heating element and exten ing around the casin E3. The nipple G is connected to the pipe D by a flexible conduit preferably in the form of a rubber hose G.

The up rend of the radiator unit is provided wit a controlvalve H connected to the space C4 through a pipe H3. The control valve is of the plug type and the valve plug is provided with. passages H and H perpendicular to each other and adapted to be rotated into different positions to cut oll` communication with the radiator element or to connect the pipe H' leading from the radiator unit, either to a pipe H passing through an opening B and leading to a source of suction such as the suction intake manifold of the vehicle engine or to a port H leadin to the atmosphere. The valve' is operated by a handwheel He projecting through an end Wall of the radiator casing A. A drip pan .J is connected tothe bottom of the pipe H* to catch any liquid passing down through that pipe.

In the preferred mode of operation of the apparatus described, the bellows element F is filled with a vaporizable liquid while the system resumably contains air or other gas. The andwheel H is rotated to connect the. enclosed space C* with the engine suction intake manifold to exhaust the air and vases therefrom. When most of the gases lhave been exhausted, the handwheel is rotated one eighth of a turn to cut off communication with the engine manifold. The pressure in the space-C* is then considerably below atmospheric and as the ressure in the hea-ting system drops beyond3 a certain point, the pressure of the surrounding atmospherehon the bellows F causes this element to partially collapse, thereby forcing some of the liquid therein intothe coil G2, where it is heated by the engine'exhaust gases contacting therewith and vaporized. The vapor generated passes upwardly through the conduit G3 into the space C* between the tubes C and C. The vapor in the space C* loses part of its heat to the air circulating through the casing A and condenses. The condensate flows by gravity tothe lower end of the radiator unit and passes down through the conduits Gra and G to the bellows and heating coil, where it is again vaporized.

The vapor pressure in the system gradually rises until the pressure is almost atmospheric. As the pressure approaches this point the bellows F correspondingly expands thereby increasing its liquid holding capacity and withdrawing an increasing amount 'of returning condensate from circulation. The` decrease in the amount of circulating fluid causes the Huid pressure in the heating s vstem to drop. The drop in pressure causes the bellows F to partially collapse and thus increase the amount of circulating fluid. The amount of heat radiating surface due to the particular construction ofthe radiating 1in C5 and the inner tube C2 is sufficient to prevent the temperature within the radiator lunit from ever rising beyond a predetermined point and prevents the pressure therein from increasing beyond atmospheric. seen that in the normal operation of my heating system, the air having been initially exhausted from the radiator unit, that the heating cycle comprises a collapsing of the bel- -lows F, an increase in the amount of fluid circulating in the system, and an increase in the fluid pressure in the system which causes the bellows to again expand.' The increased capacityT of the bellows decreases the amount of circulating fluid and thereby causes a drop of ressure in the system until an equilibrium point is reached where the amount of vaporl being condensed in the radiator unit is just equal to the amount of vapor being generated in the heatin coil.

When it is esired to render the system inoperative for heating service the valve H is .lt is thus turned to connect the space C4 with the atl V mosphere and allow the system to be filled with air. The valve is then closed and the air trapped in the system prevents the circulation of vapor as the system becomes air bound. The pressure in the system issuliicient to prevent the bellows from collapsing and any heat in the radiator unit is quickly dissipated by the radiating fins and tube sui'- faces. The heating system can be restored to service by connecting the space Cto the engine suction manifold to exhaust the air therefrom, thus creating an unbalanced force on the outer wallsof the bellows element F.

The Vaporizable liquid in use is one having a. relatively hieh boilin point at atmospheric pressure, preferably zout 300 F. and a boiling teiii'perature of about 225 F. when subjected to the amount of vacuum normally obtained by connecting the tube space to the engine manifold. A. light lubricating oily having these requisites is most desirable. The temperature of the exhaust gases passing through the pipe E and around the heating coil G2 ranges from 275 F. to 350` F. depending upon the engine opera-ting conditions. Witli these conditions the temperature in the radiator unit will be approximately 225 F. and the pressure below atmospheric.

The heatiner system disclosed herein could be modified by eliminating the bellows F when the liquid in use has a boiling point so high that it will not boil at atmospheric 'pressure when subiected to the temperatures normally existing in the engine exhaust pipe. The liquid must, however, boil under the minus pressure obtained when the air is exhausted from the heating system. In such a construction, the lower end of the heating coil is sealed to hold the vaporizable liquid and the operation is the same as before except that the system is controlled exclusively by the variations in pressure therein causing vaipor to be generated as the pressure drops su cieiitly and keeping the liquid from boiling when the pressure in the system is approximately atmospheric.

My invention is characterized by its simplicity of control,.low cost of construction and effectiveness in operation. The heating system may be incorporated in existing vehicles with little alteration in the construction thereof and by relatively unskilled labor. The use of a light lubricating oil as the cir culating medium is also advantageous in that if some of the vapor is carried over into the engine when the space C4 is connected to the intake manifold, the vapor will aid rather than injure the engine.

While in accordance with the rovisions of the statutes, I have illustrated and described the best form of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set forth in the appended claims and that in some cases certain features of my invention may be used to advantage without a corresponding use of other features. For instance, openings H2 and HIs in valve H may be eliminated. When it is desired to trap air in the heating system the air will then be drawn from the engine intake manifold through pipe H4 while the engine pistons are at rest-And, also, valve H may be adjusted to allow free communication between the suction intake manifold and the radiator element while the heatin system is in service. If the valve opening lg-I1 is made relatively small there is very little liability of vapor being sucked from the heating system into the engine when valve H is open and the enginey is in operation.

`Having Low described my invention what I claim as new and desire to secure by Letters Patent, is

1. A heating system for vehicles having an internal combustion en ine therein comprising in combination a eating element containing a vaporizable li uid, means for passing hot exhaust ases rom said engine in contact with said eating element, a radiator element connected to said heatin element, and means for automatically regu ating the amount of fluid in circulation in said system in'accordance with the iuid pressure in said system.

2. A vehicle heating system comprising in combination a heating element ada ted to contain a vaporizable iquid, means or supplying heat to said heating element, a radiator element connected to said heating element, and means for automatically regulating the amount of uid in circulation in said system in accordance with the fluid pressure in said system comprising a colla sible element containing a vaporizable liquid and having its outer walls subject to the pressure of the atmosphere.

3. A heating system for vehicles having an internal combustion engine therein comprising in combination a heating element containing a vaporizable liquid, Ameans for passing hotl exhaust gases from said engine in contact with said heating element, a radiator element having one end connected to said heating element and having its opposite end connected tothe suction intake manifold of said engine, and means for closing communication between said radiator element and said suction intake manifold. 4. A heating system for vehicles having an internal combustion engine therein comprisipg in combination a heating element-containing a vaporizable liquid, means for passing hot exhaust gases from said engine in contact with said heating element, a radiator element having one end connected to said heating element and having its opposite end connected to the intake manifold of said'engine and a control valve for connecting said ra 'ator element to said manifold or to atmosphere. l

5.V A heating system comprising a heating element adapted to contain a vaporizable liquid, a. radiator element including a fluid holding space connected to said heating element, means for supplying heat to said heating element, suction means for exhausting said fluid` holding space, and means for automatically passing a vaporizable liquid into said heating element in accordance with the pressure in said system.

6. A heating system for vehicles having an internal combustion engine therein comprising a heating coil, a collapsible element containing'a vaporizable liquld connected to said heating coil, means for passing exhaust gases in contact with said coil, a radiator element comprising an enclosed space having its upper end connected to the intake manifold of the engine and its lower end connected to said heating coil, means for normally closin the connection to the engine manifold, sai system being so arranged that the liquid holdin capacity of said collapsible element automatically increases as the pressure in the system increases and vice versa.

7 A heating system for vehicles having an internal combustion engine therein comprising a. heating coil, a collapsible element containing a vaporizable liquid connected to said heating coil, means for passing exhaust gases in contact with said coil, a radiator element mounted transversely of said vehicle and. comprising an enclosed space, said space having lts upper end connected to the intake manifold of the engine and its lower end connected to said heating coil, means for normall)r closing the connection to the engine manifold, said system being so arranged that said collapsibleelement automaticall passes liquid into said heating coil when t e pressure in the system drops'below a predetermined value.

8. A vapor heating system for automotive vehicles comprising a chamber of variable liquid holding capacity, a heating element communicating with'said chamber, and suction meansrconnected to said heating element and chamber and arranged to create a pressure differential between the inner and outer walls of said chamber to vary the liquid holding capacity of said chamber.

9. A vapor heating system for a vehicle having an internal combustion engine thereinv comprising in combination a heating element, means for passing exhaust gases from said engine in contact with said heating element, a collapsible chamber containing a vaporizable liquid communicating with said heating element, a lradiator element connected to said heating element and to the intake manifold of said engine, and means for cutting nient and said intake manifold.

10. In an automotive vehicle, the combinaoi communication between said radiator eletion` with a vapor heating'system having a vaporizable liquid therein with@ hivh boiling point at atmospheric pressure, o means connecting said heating s'ystem to the intake manifold of the vehicle engine for lowering ruary, A. D. 1928.

4 the boiling point of said liquid.

Signed at Buffalo, in the county of Erie and State of New York, this 6th day of Feb- NORMAN L. DERBY.v 

